register_cseq 13 include/linux/netfilter/nf_conntrack_sip.h unsigned int register_cseq; register_cseq 1313 net/netfilter/nf_conntrack_sip.c ct_sip_info->register_cseq = cseq; register_cseq 1341 net/netfilter/nf_conntrack_sip.c if (ct_sip_info->register_cseq != cseq)